cargo: bump syn from 1.0.89 to 1.0.90

Bumps [syn](https://github.com/dtolnay/syn) from 1.0.89 to 1.0.90.
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](https://github.com/dtolnay/syn/compare/1.0.89...1.0.90)

---
updated-dependencies:
- dependency-name: syn
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Cargo.lock

@@ -3695,9 +3695,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "1.0.89"
+version = "1.0.90"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ea297be220d52398dcc07ce15a209fce436d361735ac1db700cab3b6cdfb9f54"
+checksum = "704df27628939572cd88d33f171cd6f896f4eaca85252c6e0a72d8d8287ee86f"
 dependencies = [
  "proc-macro2",
  "quote",